Final answer:
Curl reformation services should not be combined with color services involving high concentration peroxide or ammonia, as this can lead to severe hair damage due to the hair's compromised condition after such treatments.
Step-by-step explanation:
Curl reformation services should never be combined with color services that require the use of high concentration peroxide or ammonia-based products. Hair that has been treated with these chemical color services may be left in a fragile condition, and the application of further chemical treatments, like curl reformation, could severely damage the hair structure. It is crucial to consider the chemical history of the hair and allow an adequate amount of time between different chemical services to ensure the health and integrity of the hair.